neon flashing (5th instance) Medium

Potterton neon flashing (5th instance) Fault Code

Also written as NEONFLASHING5THINSTANCE — same fault.

The Potterton neon flashing (5th instance) fault code means: your boiler's control switch is currently stuck in the reset position, preventing it from starting up normally.. It appears on 1 Potterton model in our database.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description: Selector switch in reset position. If the neon does not extinguish go to sections H and K.
Typical repair cost £120-250 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Potterton models that show the neon flashing (5th instance) fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Potterton neon flashing (5th instance) fault code information on this page is sourced and cross-checked against the official Potterton service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026